Differential Diagnosis for Chronic Lateral Ankle Swelling
Single Most Likely Diagnosis
- Chronic Ankle Sprain: This is the most common cause of chronic lateral ankle swelling due to repeated ankle injuries leading to ligamentous instability and inflammation.
Other Likely Diagnoses
- Peroneal Tendinopathy: Inflammation or degeneration of the peroneal tendons, which run along the lateral aspect of the ankle, can cause chronic swelling and pain in this area.
- Ankle Osteoarthritis: Wear and tear of the ankle joint can lead to chronic swelling, especially if the lateral aspect of the joint is more affected.
- Ganglion Cyst: A benign lump that can occur on the lateral side of the ankle, causing swelling and sometimes pain.
Do Not Miss Diagnoses
- Osteochondral Lesion of the Talus: A condition where a piece of cartilage and bone in the talus (ankle bone) becomes damaged, which can lead to chronic pain and swelling. Missing this diagnosis could lead to further joint damage.
- Infection (e.g., Osteomyelitis or Septic Arthritis): Although less common, infections in the ankle can cause chronic swelling and are critical to diagnose early to prevent serious complications.
- Tumor (e.g., Soft Tissue Sarcoma): Rare, but a tumor in the soft tissues around the ankle could cause chronic swelling and would be critical to diagnose for appropriate treatment.
Rare Diagnoses
- Rheumatoid Arthritis: An autoimmune disorder that can cause inflammation and swelling in the joints, including the ankle, though it typically affects multiple joints.
- Haglund's Deformity: A bony enlargement on the back of the heel that can cause swelling and pain, especially if it irritates the surrounding soft tissues.
- Peroneal Nerve Compression: Compression of the peroneal nerve can cause swelling and other symptoms like numbness or weakness on the lateral side of the ankle and foot.